Gradualism in Evolution not supported by genome studies (Agnosticism)

by David Turell , Thursday, October 08, 2020, 17:16 (1506 days ago) @ dhw

dhw: I don’t see how gene loss can MAKE new species, and am proposing that new genes or new functions for old genes make species, and the loss of genes is the RESULT of speciation, because natural selection roots out whatever is no longer required. Please explain why this is not feasible.

DAVID: This statement of yours is specifically totally incorrect. Behe clearly shows loss of genes speciates as does this new entry. The bold is a backward view of the process. The loss causes speciation. It can be seen as a rearrangement of genes and a restructuring of old gene expression in new gene networks of the remaining genes. […]

dhw: I haven’t read Behe, but you have told us that this is his theory. The new entry does not show that loss of genes CAUSES speciation, unless you have omitted something from the quotes. It says that all four studies “found massive gene losses….This suggests that major evolutionary transitions do not occur solely by means of tinkering with existing genes. Instead, it seems that vast numbers of existing genes are jettisoned and replaced by entirely different ones.” Do you really believe that there would be a new species if the jettisoned genes were not replaced by new ones? The existing genes that are jettisoned are not needed because they are replaced by the new ones! (dhw’s new bold)

DAVID: Your declaration of 'there must be new genes' I view as a cry of despair! The article is not edited by me to hide gene gains. In that regard, all it discussed was gene loss!!!

dhw: I wrote that the article did NOT show that loss of genes caused speciation, unless you’d missed something out. I had already bolded the relevant sentence: “existing genes are jettisoned and replaced by entirely different ones.” Do you think entirely different genes are old genes? And are you now going back to your earlier denial that new genes exist? Look again at the article: “The evolution of new genes is a subject with a substantial literature of its own […] many genes evolve de novo from non-coding sequences.” In the light of all this, why is my theory not feasible?

DAVID: Because the evidence presented does not support it for new genes. Where I agree is: new functions of old genes by reorganization of gene expression and redeveloped gene wide network associations may well be the cause of speciation.

dhw: The evidence presented emphasizes the existence of new genes, and the fact that they replace old genes. I agree that the remaining genes will be restructured. All this is an exact repeat of my proposal that speciation is caused by the “acquisition of new genes (or new functions for old genes) and loss of unwanted genes. Natural selection merely decides which genes are necessary and which are not.” However, I must stress that I am not arguing with Behe – I can only discuss the points you raise. Now please tell me why my proposal is not feasible.

Yes, we both agree new genes appear, but the evidence is still on the side that speciation involves loss of genes. To repeat: "new functions of old genes by reorganization of gene expression and redeveloped gene wide network associations may well be the cause of speciation." Your proposal covers the same ground. Our difference is I think God is doing the coding.